1. Field of the Invention
The present invention relates to a liquid level control float valve and more particularly, to an improved liquid level control float valve including an open/close valve connected to a float ball and a valve body which contains a piston member having a disc valve for opening and closing an outlet or a drain aperture of the valve body, respectively, whereby the liquid used in controlling the liquid level in the valve of the present invention originates from a low reservoir tank or a high reservoir tank installed in buildings, apartments, factory buildings, and the like.
2. Description of the Prior Art
There are many types of liquid control devices such as leveling valves, motorized valves or solenoid valves. However, these valves suffer from a number of disadvantages such as, for example, they require a power source from a reservoir tank attached thereto, and they cannot always prevent fluid flow since dregs collecting at the valves prevents the valves from tightly closing.
Furthermore, it is conventional practice in the prior art to use a float ball tap. The float ball tap is structured for closing the fluid flow by the buoyancy action of a float ball mounted to the end of a lever which is attached to a plurality of hinges. However, the float ball tap suffers from a number of disadvantages such as, for example: (1) it is difficult to prevent the fluid from leaking into the valve seat when the pressure of the fluid flow through the conduit is higher than that of the valve closed by the buoyancy action of the float ball; (2) the valve might be opened and a large volume of the fluid lost since a lever can be destroyed at the bending portion or connecting portion thereof with the float ball causing an increased buoyancy force; (3) the float ball tap must be frequently replaced; (4) since the valve of the float ball tap is continuously actuated by the buoyancy action, the tensibility of the lever is gradually replaced; and (5) it is difficult for the float ball tap to control the fluid level when the ball tap is attached to reservoir tanks at locations with different heights, for example, at the top of buildings with different heights.
According to the U.S. Pat. No. 4,741,358 entitled "liquid level control float valve" issued the inventor of the present invention, the liquid level control float valve disclosed includes an open/close valve disposed in a valve body which is substantially operated by the rising or lowering of a float ball. However, if a drain aperture of the valve body has a large diameter, a lever connected to the float ball has to be extended or the float ball has to be enlarged. Therefore, the reservoir tank has to be enlarged.